Advanced, single-chip architecture provides high performance, long battery life. The heart of the TI-68 is a single, advanced calculator integrated circuit. Fabricated in a high-performance silicon-gate CMOS technology that dissipates very little power, this four-bit microcomputer is designed specifically for calculator applications. The highly integrated chip contains the TI-68's CPU and memory as well as its 540- pixel display-driver and keyboard- interface circuitry. To prolong battery life without com- promising high-performance operation, the TI-68 chip operates in multiple modes. In its high-speed calculating mode the chip consumes 220 microamps; in its power-saving idle mode the chip drives the display and reads the keyboard for inputs but con- sumes just 23 microamps. The calcula- tor maintains the high contrast and wide viewing angle of its liquid crystal display over the life of the battery. Texas Instruments manufactures the TI-68 under rigid quality standards. We test the calculator and its components to assure reliable service that extends far beyond the calculator's one-year limited warranty. In rigorous qualification and produc- tion tests the TI-68 has survived condi- tions that simulate reasonably expected use and reasonably expected abuse: Extended-storage temperatures that range from -40 to 70 degrees Celsius (-40 to 158 degrees Fahrenheit). Operating temperatures that range from zero to 40 degrees Celsius (32 to 104 degrees Fahrenheit). Steam-bath conditions (a tempera- ture of 50 degrees Celsius - 122 degrees Fahrenheit - with 95 percent relative humidity). Drop tests conducted from desktop height to cause an impact on each sur- face of the calculator. Keystroke actuation tests (500,000 actuations per key) and more. 0 4